Good old sandpaper did the trick. Beforehand we ran them through the bobbin sander, whilst stickers were chiselled off.
Some technical stuff about sandpaper (abrasive paper): lower numbers (80) are more coarse, higher numbers smoother (360). We used pretty low numbered sheets, best for rapid removal.
Sadly, the Illustrator file which was correctly exported as a .emf file wasn't able to be read by 2D Design for some reason, leaving Andrew and ourselves baffled. Not sure why. Very frustrating. Although transfer from Illustrator isn't strictly recommended, there are guidelines such as using fine lines (0.25), having no fills, no layers, and other little things, all of which should have been ok. Hmm.
This isn't the last you'll hear about the Victate skateboards. We'll be back!